"Pre-Safe Functions Limited" while test-driving




I was driving in M mode, shifting between 3-4 gear at 60-80 mph. Did not redline at all. Car was warmed from about idle and about 15 mins of driving.
I searched online and this seems like a rare event, and I did not see anyone post with a C63 from a brief search. I have seen limp mode in my BMW 335i, but the C63 did nothing. Does anyone know if this a major problem for this car?
Is this a sign that I should try the other C63 at the dealer (a 507 Edition)?
I was driving in M mode, shifting between 3-4 gear at 60-80 mph. Did not redline at all. Car was warmed from about idle and about 15 mins of driving.
I searched online and this seems like a rare event, and I did not see anyone post with a C63 from a brief search. I have seen limp mode in my BMW 335i, but the C63 did nothing. Does anyone know if this a major problem for this car?
Is this a sign that I should try the other C63 at the dealer (a 507 Edition)?
It's also complicated. My advice is to not give up on C63 but avoid Distronic Plus like the plague.
I have had no problems with it at all, only 3K miles but nothing in that time.
Last edited by bjonesmd; May 5, 2014 at 09:44 PM.




I would not want this to happen when I am hours from home.
I would not want this to happen when I am hours from home.
I have been reading the forums awhile and this is the first time I have heard of this problem (I have not done a search). You may want to check the technical forums. However keep in mind that only the few with problems will likely post threads. The forums tend to spotlight problems, without a real reference point for frequency of occurence (with some exceptions).
FWIW, I am very happy with Dystronic Plus, I only wish it had more features, such as those available on the E-class.
That said, OP, it's clear the system suffered a major failure and it's probably a rare event in itself. It's not something that you would expect can be overridden with a setting. That's because Distronic is tied into the brakes. If it senses you are about to rear end something, it will slam on the brakes for you. Obviously any computer control system that has access to the brakes needs to fail very safely. That's why this particular failure puts the car out of service. Again, it's probably rare. But it's another reason to avoid Distronic IF you don't expect to drive the car with it engaged. My driving style is as manual as is possible (and I've had Distronic on past cars) so I'd consider it an unwanted complication. But you may love it, in which case focusing on it's failure is not the best approach.
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I get that warning all the time - evrytime I turn stability off. Seriously, turning stability completely off should disable pre-safe functions. I get a big orange warning to that effect everytime.
Distronic won't work when stability is in sport, but the blind-spot and other pre-safe features do.
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I get that warning all the time - evrytime I turn stability off. Seriously, turning stability completely off should disable pre-safe functions. I get a big orange warning to that effect everytime.
Distronic won't work when stability is in sport, but the blind-spot and other pre-safe features do.

I would not want this to happen when I am hours from home.
ESP in sport mode turns distronic off and disables some pre-safe
ESP off goes further and turns the vast majority of pre-safe off
Turing off stability (hence distronic and the vast majority of pre-safe) might have helped alleviate the situation, gained insight into the problem and perhaps allowed the car to drive to the dealer
OP - how did the car make it back - tow?




We were not changing any functions at the time, ESP was on, and the salesman was just playing with the Nav. The salesman and my wife did not realize anything was wrong until we coasted off the highway and I parked the car because the gas had no effect.

Anyone have an idea what causes errors like this?
Thanks in advance
Oyvind
Its very odd indeed, not to mention dangerous. I can only imagine if trying to pass a 18 wheeler, and suddenly you have no power, and a car is coming against you. You judge a situation up front before committing to the passing of the long truck, based on the distance to the car coming against you and approx. speed he would have, and the acceleration of your own car.
The dealer has had the car from late Friday afternoon, but probably didnt start working on till yesterday. I will post here any new information i get.
did you get your car back? do you know what was the issue? I am having similar problems with my 2007 R350 it eventually stalls, engine idle but you can coast.





